Bill acceptors have become ubiquitous in today's world. Various types of bill acceptors can be found, for example, on gaming machines, vending machines and change machines. In a conventional bill acceptor, a consumer inserts a bill into a horizontal slot. The bill acceptor draws in the bill to analyze whether it should validate the bill. If the bill acceptor is unable to validate the bill, the bill acceptor pushes the bill back out to the consumer, without giving any credit for the bill. If the bill acceptor validates the bill, it passes the bill on for stacking with other previously validated bills in a cash box. It also credits the consumer for the bill, allowing the consumer to play a game, purchase a product, receive change, etc.
It has been learned that some consumers attempt to defraud bill acceptors by withdrawing their bills after having received credit for them. One common ploy, sometimes called “stringing,” involves using a very fine “string,” such as fishing line. The fishing line is used by fraudulent consumers because it is thin enough that it may not be detected by the bill acceptor's optical sensors. The fraudulent consumer attaches a double layer of transparent tape across the length of a bill and attaches the fine fishing line to the bill with the tape. The tape is transparent so that it will not prevent the bill acceptor from locating the required images on the bill for validation. After the bill is validated by the bill acceptor and stacked in the cash box, the consumer pulls the string back through the bill acceptor. The double layer of tape unfolds from the bill. When the fraudulent consumer can reach the tape, he then pulls on the tape and recovers the bill. Thus, the consumer receives credit for the bill without actually giving the bill to the machine operator.
Using video and security guards is an expensive way to try to prevent this fraud. A security guard monitoring the situation on a real-time basis is likely too expensive. Although reviewing past video surveillance only if and when a problem is discovered is less expensive, it is unlikely to catch each fraudulent transaction. Even if such a system did discover a past fraudulent transaction, the perpetrator is likely long gone by the time the problem has been reviewed on video.
Deterrents within the bill acceptor itself might seem to hold more promise, but until now, such systems have been less than satisfactory. A need exists for an effective device and method to discourage and prevent fraudulent use of bill acceptors.